1. Field of the Invention:
This invention relates to a process for manufacturing a finished component from a memory alloy.
2. Description of the Prior Art:
Shaped memory alloys of the Ni/Ti type, and their properties, are known from the literature (e.g. C. M. Jackson, H. J. Wagner and R. J. Wasilewski, 55-Nitinol-The alloy with a memory: its physical metallurgy, properties and applications, NASA SP5110, pages 19-21).
In the manufacture of finished components from memory alloys based on nickel and titanium, processing starts, as a rule, from appropriately preshaped semifinished products, such as rod, tube, strip and sheet material. In principle, machining of the metal-cutting type can be employed to convert suitable sections of the selected starting material into the final product.
Attempts have certainly also been made to employ conventional hot-working methods for this purpose, such as die-forging, etc.
Having regard to the brittleness and hardness, and to the inadequate ductility of these alloys, cutting-type machining is unsuitable and uneconomical, especially for mass production. On the other hand, conventional hot-shaping processes have hitherto been unsuccessful, since very high deformation forces were needed in these processes, and the structure of the material was extensively destroyed in the course of the working operation. There is accordingly an outstanding need for the development of new, inexpensive processes, especially with regard to the very wide range of possible applications of finished components made from memory alloys as connecting elements.